Dive One Of The Largest Clear Water Caverns
One of the first distinctions for a recreational diver to understand is between cavern diving and cave diving, both of which generally require additional certifications. The technical definition of a cavern is that the primary light source is the sun (even if you’re using supplemental light) and that you should be able to see the exit at all times. Once you’re past that zone, you’re in a cave—and in much more serious territory.
The Blue Grotto Dive Resort in Williston, Fla., offers divers the perfect option, with a large wide-open cavern on one side, and a pretty good-sized cave on the other. “On the cavern side, the area between 60 and 100 feet deep is technically called a cave—but the real cave goes for miles and miles,” instructor certifier Kurt Huber says. “We allow open water certified divers all the way down to 60 feet, because there is an air bell safety feature at 30 feet as an emergency stop.” While the cavern side of Blue Grotto can be dived with basic open water certification, the cave side requires cave diver certification and accompaniment by a qualified guide. If it’s your first dive there, you’ll need to pass a skills/ability screening.
One of the main draws to the Blue Grotto is its year-round 72-degree temperature and 100-foot visibility, thanks to the crystal-clear spring water. “People come from all over the world to learn to dive here,” Huber says. “No waves, no currents, and you don’t need a boat.”
Dive the Third Longest Underwater Cave
Mexico’s Yucatan Peninsula features its own version of cavern and cave diving in cenotes (pronounced “say-NO-tays”), which are deep, water-filled sinkholes in the limestone created by the collapse of an underground cavern. Recreational divers can dip into Cenotes Dos Ojos, the world’s third-longest underwater cave system, as a way of getting comfortable in an overhead environment.
Dos Ojos, which translates to “two eyes” in English, refers to two neighboring cenotes set inside the jungle, which connect into a very large cavern zone shared between the two. A section of the cenote, called the Barbie Line, gives divers a lot of space to swim around huge formations such as stalactites, stalagmites, and columns. The Bat Cave is the darker of the two dives, leading around an air-filled bat cave with little daylight entering.
The water is exceptionally clear, with 300-foot-plus visibility, and maintains a constant temperature of 79 degrees year round. If the underwater scenery looks familiar, it’s probably because the Dos Ojos underwater cave system was featured in the 2002 IMAX film “Journey into Amazing Caves,” the 2005 movie “The Cave,” and the 2006 BBC/Discovery Channel series “Planet Earth.”
Dive a Cave Less Explored
Dive instructor Tom Crisp of New Zealand-based Global Dive describes cave diving as one of mankind’s last frontiers. To dip into his favorite cave dive, Blue Creek Resurgence, definitely requires a pioneering spirit—and they still run an expedition every year to explore the unexamined depths. The site is located at the base of Mount Owen in the Kahurangi National Park, but let’s say access is a bit logistically challenging: about seven miles of gravel road, followed by a 1.5-mile hike up the side of the mountain carrying your equipment. Oh, and don’t forget that all the equipment then needs to be ziplined into the entrance before you plunge into the brisk, 43 degree water.
“Once you’re in the water, the cave quickly narrows down to a restriction where divers need to scrape and sometimes dig their way through to the other side,” Crisp says. “But the rewards are tenfold, as the cave opens up into four large tunnels heading in all directions.” A swim into the deep section of the cave brings you into a chamber called the Cathedral, which is 150 feet deep at the floor where you enter. Beyond the Cathedral, the cave plummets to a depth of 230 feet with another restriction to navigate.